| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20180423105003.9004-25-enric.balletbo@collabora.com>
Date: Mon, 23 Apr 2018 12:50:00 +0200
From: Enric Balletbo i Serra <enric.balletbo@...labora.com>
To: architt@...eaurora.org, inki.dae@...sung.com,
thierry.reding@...il.com, hjc@...k-chips.com,
seanpaul@...omium.org, airlied@...ux.ie, tfiga@...omium.org,
heiko@...ech.de
Cc: dri-devel@...ts.freedesktop.org, dianders@...omium.org,
a.hajda@...sung.com, kernel@...labora.com,
m.szyprowski@...sung.com, linux-samsung-soc@...r.kernel.org,
jy0922.shim@...sung.com, rydberg@...math.org, krzk@...nel.org,
linux-rockchip@...ts.infradead.org, kgene@...nel.org,
orjan.eide@....com, wxt@...k-chips.com, jeffy.chen@...k-chips.com,
linux-arm-kernel@...ts.infradead.org, wzz@...k-chips.com,
hl@...k-chips.com, jingoohan1@...il.com, sw0312.kim@...sung.com,
linux-kernel@...r.kernel.org, kyungmin.park@...sung.com,
Laurent.pinchart@...asonboard.com, kuankuan.y@...il.com,
hshi@...omium.org,
Enric Balletbo i Serra <enric.balletbo@...labora.com>
Subject: [RESEND PATCH v6 24/27] drm/rockchip: psr: Avoid redundant calls to .set() callback
From: Tomasz Figa <tfiga@...omium.org>
The first time after we call rockchip_drm_do_flush() after
rockchip_drm_psr_register(), we go from PSR_DISABLE to PSR_FLUSH. The
difference between PSR_DISABLE and PSR_FLUSH is whether or not we have a
delayed work pending - PSR is off in either state. However
psr_set_state() only catches the transition from PSR_FLUSH to
PSR_DISABLE (which never happens), while going from PSR_DISABLE to
PSR_FLUSH triggers a call to psr->set() to disable PSR while it's
already disabled. This triggers the eDP PHY power-on sequence without
being shut down first and this seems to occasionally leave the encoder
unable to later enable PSR. Let's just simplify the state machine and
simply consider PSR_DISABLE and PSR_FLUSH the same state.
Signed-off-by: Tomasz Figa <tfiga@...omium.org>
Signed-off-by: Kristian H. Kristensen <hoegsberg@...omium.org>
Signed-off-by: Thierry Escande <thierry.escande@...labora.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@...labora.com>
Tested-by: Marek Szyprowski <m.szyprowski@...sung.com>
---
drivers/gpu/drm/rockchip/rockchip_drm_psr.c | 80 +++++++--------------
1 file changed, 24 insertions(+), 56 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
index 9376f4396b6b..1a6157ffecec 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
@@ -20,19 +20,13 @@
#define PSR_FLUSH_TIMEOUT_MS 100
-enum psr_state {
- PSR_FLUSH,
- PSR_ENABLE,
- PSR_DISABLE,
-};
-
struct psr_drv {
struct list_head list;
struct drm_encoder *encoder;
struct mutex lock;
bool active;
- enum psr_state state;
+ bool enabled;
struct delayed_work flush_work;
@@ -73,52 +67,22 @@ static struct psr_drv *find_psr_by_encoder(struct drm_encoder *encoder)
return psr;
}
-static void psr_set_state_locked(struct psr_drv *psr, enum psr_state state)
+static int psr_set_state_locked(struct psr_drv *psr, bool enable)
{
- /*
- * Allowed finite state machine:
- *
- * PSR_ENABLE < = = = = = > PSR_FLUSH
- * | ^ |
- * | | |
- * v | |
- * PSR_DISABLE < - - - - - - - - -
- */
- if (state == psr->state || !psr->active)
- return;
-
- /* Already disabled in flush, change the state, but not the hardware */
- if (state == PSR_DISABLE && psr->state == PSR_FLUSH) {
- psr->state = state;
- return;
- }
+ int ret;
- /* Actually commit the state change to hardware */
- switch (state) {
- case PSR_ENABLE:
- if (psr->set(psr->encoder, true))
- return;
- break;
-
- case PSR_DISABLE:
- case PSR_FLUSH:
- if (psr->set(psr->encoder, false))
- return;
- break;
-
- default:
- pr_err("%s: Unknown state %d\n", __func__, state);
- return;
- }
+ if (!psr->active)
+ return -EINVAL;
- psr->state = state;
-}
+ if (enable == psr->enabled)
+ return 0;
-static void psr_set_state(struct psr_drv *psr, enum psr_state state)
-{
- mutex_lock(&psr->lock);
- psr_set_state_locked(psr, state);
- mutex_unlock(&psr->lock);
+ ret = psr->set(psr->encoder, enable);
+ if (ret)
+ return ret;
+
+ psr->enabled = enable;
+ return 0;
}
static void psr_flush_handler(struct work_struct *work)
@@ -126,10 +90,8 @@ static void psr_flush_handler(struct work_struct *work)
struct psr_drv *psr = container_of(to_delayed_work(work),
struct psr_drv, flush_work);
- /* If the state has changed since we initiated the flush, do nothing */
mutex_lock(&psr->lock);
- if (psr->state == PSR_FLUSH)
- psr_set_state_locked(psr, PSR_ENABLE);
+ psr_set_state_locked(psr, true);
mutex_unlock(&psr->lock);
}
@@ -171,6 +133,7 @@ int rockchip_drm_psr_deactivate(struct drm_encoder *encoder)
mutex_lock(&psr->lock);
psr->active = false;
+ psr->enabled = false;
mutex_unlock(&psr->lock);
cancel_delayed_work_sync(&psr->flush_work);
@@ -180,8 +143,13 @@ EXPORT_SYMBOL(rockchip_drm_psr_deactivate);
static void rockchip_drm_do_flush(struct psr_drv *psr)
{
- psr_set_state(psr, PSR_FLUSH);
- mod_delayed_work(system_wq, &psr->flush_work, PSR_FLUSH_TIMEOUT_MS);
+ cancel_delayed_work_sync(&psr->flush_work);
+
+ mutex_lock(&psr->lock);
+ if (!psr_set_state_locked(psr, false))
+ mod_delayed_work(system_wq, &psr->flush_work,
+ PSR_FLUSH_TIMEOUT_MS);
+ mutex_unlock(&psr->lock);
}
/**
@@ -250,8 +218,8 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder,
INIT_DELAYED_WORK(&psr->flush_work, psr_flush_handler);
mutex_init(&psr->lock);
- psr->active = true;
- psr->state = PSR_DISABLE;
+ psr->active = false;
+ psr->enabled = false;
psr->encoder = encoder;
psr->set = psr_set;
--
2.17.0
Powered by blists - more mailing lists